Journal articles: 'Big Sandy Area' – Grafiati (2024)

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Big Sandy and Clinesmith oil fields are located about five miles apart along the boundary between Woodson and Wilson counties in southeast Kansas. They are located on the Pennsylvanian Cherokee Platform and were discovered almost 60 years apart in 1923 and 1982 respectively. Both fields produce from Desmoinesian lower Bartlesville sandstone reservoirs at shallow depths (1,100 to 1,200 ft) from reservoirs that have been interpreted as “shoestring sandstones.” However, if Big Sandy is restricted just to the area of Section 23 and the southeast quarter of Section 22, T26S, R14E where it offers the best wireline log control, the two fields have different orientations. Big Sandy has a southwest/northeast trend almost perpendicular to Clinesmith Field, which trends from north-northwest to southward. Big Sandy Field has a more elliptical shape with a length-to-width ratio of 3:1, vs. 10:1 for the very linear Clinesmith Field. Another major difference between the two fields is that the gamma-ray logs in and along the Clinesmith reservoir trend generally have a fairly well-defined fining-upward trend characteristic of a fluvial channel system. Big Sandy logs, in contrast, show much more variability from well to well. Petrographically the two fields have characteristics that are both consistent and strikingly different. Both reservoirs have a consistent very-fine to fine sand grain size with fair to well-sorted grains. Both also have texturally immature grains that are angular to subrounded with nearly identical compositions of abundant quartz, and associated plagioclase, biotite, muscovite, plant debris, and metamorphic rock fragments. Thus, the Bartlesville Sandstone in both fields had the same nearby sediment source terrain comprised mainly of granites and metamorphic rocks. Each field also produces mainly from primary interparticle porosity in sandstones with loosely packed grains where total porosity locally exceeds 20%. A difference is that, although both fields contain common shale clasts, those in Big Sandy Field tend to be much larger and occur with common siderite (iron carbonate) nodules. Siderite is rare in Clinesmith Field although a few small nodules occur in the associated floodplain shales, along with carbonaceous partings. Also present in Big Sandy’s reservoir are other iron-bearing minerals such as glauconite, pyrite, and chlorite, although all of these are far less common than the siderite. Such an abundance of iron-rich minerals can occur in marginal marine environments such as estuaries where a reducing diagenetic environment forms just below the sediment/water interface. In contrast, well-oxygenated fluvial systems generally contain any iron in highly oxidized forms such as hematite and limonite. From these observations, it appears that Big Sandy’s reservoir interval was deposited in an estuarine (coastal marine) setting with diverse localized depositional environments whereas the Clinesmith reservoir represents a nearly straight, south-flowing fluvial channel and adjacent floodplain, with no marine influence on deposition.

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Abstract Mangrove ecosystems have various services, one of them being a barrier to strong waves and seawater currents. Growing mangroves in the physical environment with sandy soil, high differences between high and low tides, big waves, and strong seawater currents such as in the Bali Sea under a highway interchange is not easy. To cope with this kind of less-understood environmental condition, the experiment planting was done by applying three kinds of planting techniques: mangrove incubator (guludan), strip line planting, and cluster planting using the mangrove (Rhizophora mucronata) seedlings having sufficient tolerance to high salinity and sandy soils. Two months after planting, the tree planting techniques showed a high percentage of survival of planted seedlings (PSS=100%) and well healthy growing performance of seedlings (no infected by pest and disease), the average increments of seedling stem diameter ranged from 0.73 to 1.15 mm, height ranged from 8.70 to 10.98 cm, and the number of leaves ranged from 1.08 to 1.45 pieces in a month. Furthermore, the best planting technique was the mangrove incubator (guludan) in terms of stem diameter growth, while the strip line and cluster techniques were the best in terms of seedling height growth.

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In this paper, the shrub windbreak and sand-fixing sand barrier of Bairin Youqi in Chifeng in the east of Horqin Sandy Land is the research object, three different types of plant barriers including hedysarum laeve grid sand barrier, Salix gordejevii and hedysarum laeve grid sand barrier and caragana and hedysarum laeve patch sand barrier are respectively selected, and the shifting sandy land is selected as a contrast at the same time to study its influence on the soil moisture of sandy land in the method of field locating observation method from early May to late September of 2005. Except for the contrasted sandy land, the monthly average soil moisture in each layer of plant sand barrier presents a fluctuation trend. The monthly change trend of soil moisture in the 10~20cm soil layer of hedysarum laeve grid sand barrier is the same as that of caragana and hedysarum laeve patch sand barrier. The soil moisture in 20~40cm soil layer of the three plant barriers in every month shows a big change, with the fluctuation range larger than the contrasted sandy land. The 20~60 cm soil layer is the area where the roots of sand barrier plant are centralized, therefore, the soil moisture in the root intensive area is reduced. The monthly change trend of soil moisture in 60~80cm soil layer of hedysarum laeve grid sand barrier, caragana and hedysarum laeve patch sand barrier is the same as that of the contrasted sandy land. The monthly change trend of soil moisture in the 80~100 soil layers is basically same. The minimum value of monthly average soil moisture of all kinds of plant sand barriers appears when the contrasted sandy land is 1.40%, and the maximum value appears when caragana and hedysarum laeve patch sand barrier is 4.79%, 3.4 times higher than the contrasted sandy land. The annual dynamic condition of soil moisture can be divided into: consumption period from April to June, supply period from July to August, stable period in September, which shows that the plant sand barrier is favorable for increasing the soil moisture.

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Abstract Geoecology is a landscape study combined with the social and environmental aspect. The study aims to identify Geoecology of coastal Manado, North Sulawesi. Identification of coastal Geoecology using Landsat 8 supported by SRTM. Data was collected by field survey and taking aerial photo using UAVs. The field survey was conducted to capture the documentation and in-depth interviews. The research method is the interpretation of remote sensing imagery. Data from image interpretation collaborated with field survey data. The results showed that there are three types of coastal that is sandy, rocky and muddy. The sandy comes from karst hills and volcanoes. The rocky and karst hills come from volcanic material that has the character of a big wave. The muddy affected by the presence of the river that carries materials from structural hills. Geoecology based coastal area management is expected to be instrumental in structuring regional integrated and planned.Key words: Geoecology, Landsat, Coastal, North Sulawesi

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Based on the data of China’s economic and social big data platform from 2000 to 2019, this paper studies and analyzes the development status and influencing factors of desertification in Maowusu sandy land in China. Based on the exploratory analysis (EFA) and the dummy variable regression model (DVRM), the research result shows that the annual precipitation is the main climate factor affecting the vegetation coverage in this area. And for every 100 mm increase in annual precipitation, vegetation coverage will increase by 10%. In addition, the annual average temperature also has a significant impact on the vegetation coverage. For every 1 °C increase in the annual average temperature, the vegetation coverage will increase by 2.5%. Analysis of policy factors shows that the policy effects of the 2005 National Desert Control Plan (2005-2010) and the 2011 National Desert Control Plan (2011-2020) etc. can increase vegetation coverage by 3.4% and 4.7%respectively compared with the base period level in 2000. The study reveals the important role of climate and policy factors in the reversion of desertification in Maowusu sandy land. The study is of great significance and value to desertification management and related policy-making in China.

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The state of Mississippi is one of the least botanically explored areas in the eastern United States. A floristic survey of Choctaw County, Mississippi, was conducted from November 2009 through November 2017 in order to document the vascular flora and describe its plant communities. The county is located in the central portion of the state within the North Central Plateau physiographic region, an area dominated by dissected uplands with acidic to circumneutral sandy-clay soils. Three major river basins occur in the county, including the Big Black River, Noxubee River, and Pearl River. A total of 950 vascular plant species (958 taxa including varieties, subspecies, and recognized hybrids) was recorded. Three-hundred thirteen of these taxa were new county records. Twenty-eight species of special concern as designated by the Mississippi Natural Heritage Program were documented. Approximately 15 percent of the flora is considered non-native to the United States. Eight primary plant communities are also described.

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The estimation of soil thermal resistivity is essential for many types of big engineering projects because of the required knowledge about subsurface transmission of either heated fluids or high power currents. Thermal conductivity measurements were carried out at 12 locations, eight measurement point locations in South Kalimantan, the Sapu Angin hill region, sub-district Penyipatan and four points in the area of Kampung Baru, sub-district Pelaihari made at 2-3 variations in depth of 50 to 100 cm, which adjusted to the ability of the soil drilling support equipment to make holes in the soil. Samples were also collected from the locations for physical parameters description that influences thermal resistivity, subjected to grain size distribution and compaction analysis. The calculation of thermal conductivity is done by using CT-Lab software ver. 1.0.2 with a sensor resistance value of 82.69 ohms / m, heater voltage 4.0 V, and heater power 4.3857 W/m. The results show that the thermal conductivity values range from 0.593 to 3.239 W/mK. For the Sapu Angin hill region, sub-district Penyipatan, soil layers are generally in the form of sandy-clay (λ> 1.2 W/mK), but at some points, the value of thermal conductivity in these layers have decreased (λ <1.2 W/mK) due to rainwater infiltration (BH-02, BH-03, BH-04, BH-05, and BH-07). The infiltration causes weakening or loosening of bonds between the constituent particles of the soil. While in the area of Kampung Baru sub-district Pelaihari, the soil layer is generally in the form of sandy-clay, which has not well compacted (BH-08, BH-10, BH-12) with high water content (BH-09).

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By seed surfaces according to the information the Federal Bureau of Statistics and the Institute of Statistics Republic of Srpska of the total area under vegetables potatoes occupies 57% sowing area, so that after the corn and wheat, potatoes the most important agricultural plant in Bosnia and Herzegovina. Most are lighter types of land - permeable, loose, sandy-humus and sandy-clay ground with crumb structure, rich in mineral and organic matter, with favorable water – air characteristics. Does not match his tough swampy lands with a high level of underground water. Tolerate acid soil reaction, and the optimum pH is 5,4-6,5. Given that the area of Tuzla canton mainly acid soil with pH values from 4.5 to 5.5 made the production of a sample on the plot that had a pH value of 4.6 as a material for the reparation of land or quality of calcification was Fertdolomit in order to increase in pH, after you apply Fertdolomit analysis has found that the increased pH value to 5.8. Calcification is a measure of repair of chemical properties of soil, primarily reducing its acidity, ie. bringing the pH value to the optimum level for the cultivation of certain plant species calcium use of fertilizers. At the same time, this measure of the repair water-air, mechanical, physical and biological properties of soil. Reflected in the potatoes plant in four different variants: the control, with the use of 40 t / ha of manure, the use of 40 t / ha manure and NPK 7:20:30 400 kg / ha and the use of manure 40 t / ha, NPK 7:20: 30 in the amount of 400 kg / ha with supplements Fertdolomit in the amount of 3 t / ha. The results reflected a big point to the importance of calcification in the production of potatoes.

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Field studies at the Lawther - Deer Park Prairie Preserve, an area of approximately 21 ha (51 acres) of the Gulf Coast Prairies and Marshes vegetation area, have resulted in a description of the vegetation associations and an annotated checklist of the vascular flora. Six plant community associations occur on the property: (1) the Upper Texas Coast Ingleside Sandy Wet Prairie; (2) Eastern Gamagrass - Switchgrass - Yellow Indiangrass Herbaceous Vegetation; (3) Gulf Cordgrass Herbaceous Vegetation; (4) Texas Gulf Coast Live Oak - Sugarberry Forest; (5) Little Bluestem - Slender Bluestem - Big Bluestem Herbaceous Vegetation, and (6) Natural Depressional Ponds. The checklist includes 407 species belonging to 247 genera and 86 families. Forty-six species are non-native. The best-represented families (with species number following) are Poaceae (84), Asteraceae (68), Cyperaceae (33), and Fabaceae (19). West Gulf Coastal Plain (eastern Texas and western Louisiana) endemics include Helenium drummondii, Liatris acidota, Oenothera lindheimeri, and Rudbeckia texana. One Texas endemic, Chloris texensis, a Species of Greater Conservation Need, is present. Other noteworthy species are Andropogon capillipes, Digitaria texana, and Platanthera nivea.

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Landslides are the most common geological phenomenon in Indonesia.The event is damage to public infrastructure, and fatalities was a big impact. Therefore, mapping the geometry of landslides is a part of the mitigation effort possible by geophysical methods. In this research, we applied seismic refraction tomography (SRT) to study the geometry of the sliding zone from the landslide event.TheNational Disaster Management Authority reported that the area was frequently occurring landslide disaster, i.e. 2018, 2019 and 2020 which caused the public infrastructure and obstructed the road access from the central to the west of Aceh. The SRT was measured in two profileslong the road.Data measurements were conducted on the side of the Babahrot - GayoLues road section that had experienced landslides.Measurements were made using the Seismograph PASI 16S24-P and 24 geophones to obtain a 92-meterlong profile with 2 meter spacing between the geophones. P-wave velocity data modeling is done using ZondST2D software.The results of modeling profiles 1 and 2 describe three different subsurface layers.The SRT profile 1 model consists of slate (0.2 - 0.7 km/s), clay (0.8 - 1.3 km/s), and sandy clay (1.4 - 1.9 km/s).While, the model of profile 2 consists of slate (0.5 - 1.0 km/s), clay (1.1 - 1.6 km/ s), and sandy clay (1.7 - 2.5 km/s).The contrasting wave velocity model shows that the SRT method can be used in landslide studies as a reference in determining the mechanism of the landslide system.

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The study was conducted in the commune of Bagaroua, (Tahoua region). The Tahoua area has agro-climatic characteristics favorable to agricultural production. This area is now threatened by the rapid degradation of its natural resources due to climatic hazards and human activities. It is in this context that the present study proposes to analyze the perceptions of farmers on land degradation and the adaptation strategies of producers faced with the impact of this degradation. The data was collected by interview using a questionnaire submitted to 254 agricultural producers sampled using the formula n=t&sup2; *p*(1-p) /m&sup2;. The results showed that agricultural producers clearly perceive the manifestations of soil degradation by the appearance of glacis with percentages by 66% of respondents; formation of &ldquo;erosion&rdquo; ravines (13.17%); presence of pebbles and sandy bulge (10.07%). Farmers perceive the impacts of this soil degradation through parameters such as the reduction in cultivable areas (12%); attacks by crop enemies (7%); increased food insecurity (32%); the influx of able-bodied young people to big cities (11%) inside and outside the country and delinquency (6%). This situation puts the population in a situation of extreme poverty (16%), indebtedness (8%) and conflicts between households (8%). Faced with this shock, producers adopt adaptation strategies, the most widespread of which are, among others, the use of water and soil conservation techniques, the use of organic and mineral manure, the use of improved varieties early.

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The use of green infrastructure (GI) for urban stormwater management has become a big industry, with cities like New York and Philadelphia planning to invest more than a billion dollars over multiple decades into this distributed approach to runoff reduction. Throughout the northeast US, GI systems are typically sized to fully capture all runoff generated within their tributary areas during approximately 90 percent of all wet weather events occurring annually (e.g., [Formula: see text] 25–30[Formula: see text]mm of precipitation). Though many claim that retrofitting such GI systems into urban landscapes will also help cities adapt to climate change, few researchers have actually attempted to document GI facility performance during more extreme precipitation. In this study, the stormwater capture performance of a bioretention facility located in Queens, New York City was evaluated under non-extreme and extreme precipitation conditions occurring between 2011 and 2014, including Hurricane Irene and Superstorm Sandy. Performance was found to be highly variable from event to event. The site rarely ponded, and overflowed only once (during Irene), for a short time (e.g., 10[Formula: see text]min), generating an insignificant volume (0.085[Formula: see text]m3) of overflow, likely because of the high infiltration capacity of in-situ, sandy soils and the facility’s low hydraulic loading ratio (3.8:1). Though the facility was able to infiltrate nearly all the runoff that it receives through its inlet, field monitoring suggests that site performance is often hindered by inlet bypass, not soil saturation or overflow. The site captures 70, 77, and 60 percent of all runoff generated within its tributary area during all events ([Formula: see text]), just the non-extreme events ([Formula: see text]), and just the extreme events ([Formula: see text]). The facility also regularly receives and infiltrates runoff originating outside of its designed tributary area. A regression analysis suggests that storm duration, total amount of precipitation and peak-hourly intensity are significant predictors (p-value [Formula: see text]) of, and negatively correlated with, the facility’s stormwater capture performance. The analysis also anecdotally suggests that performance might improve as vegetation gets established and/or as the frequency of maintenance visits are increased. Though this study suggests that this facility does attenuate a significant amount of runoff extreme precipitation, future work will investigate factors other than the climate which could be triggering inlet bypass occurrence, in particular GI maintenance frequency.

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Carrying out its assignment Poltava-city green belt bottomland forests with short-term flooding, has significant anthropogenic impact, needs constant research of forest biogeocoenosis present day condition. There have been done the complex research of bottomland forests with short-term flooding which are located in the range of Poltava-city green belt. Forest types according to O. L. Belgard have been noted. Soil and geobotanical characteristics, soil sections macromorphological peculiarities have been given, results of soil water extracts analysis in the investigated forestry have been noted. Throuout the complex researches of all components of forest biogeocoenosis the learning of forest and environment coorelation that is due to anthropogenic effect is topical. Especially it concerns the big cities green belt of industrial regions that suffer from the human direct influence or indirect consequences of his living. Thereby the National special-purpose program «Forests of Ukraine» for 2010–2015 was approved the aim of which is a complex study of this category of forest-steppe zone forest biogeocoenosis. For this reason was made an accent to investigate all-round the Poltava-city green belt forests related to Poltava Region throuout the regional special-purpose program of forestry integrated development «Poltava region forests by 2015». To identify the soil and geobotanical characteristics of biogeocenosis and physical and chemical piculiarities of bottomland forests with short-term flooding adaphotop we will consider the most typical sample plots of different plantations according to its forest stand that grows in relatively identical conditions. Forest areas of Poltava-city green belt belongs to the eastern soil and climatic forest-steppe zone of Poltava Region and is situated in forest-stepp belt of Left bank of Dnipro inside the Dnipro and Donetsk dimple. The most common soils are deep, low humic chernozem and middle clay-loam soil. There are mulch and sandy, agrilloarenaceous soils in river valleys. The picture of exploration area ground structure looks in such a way. The most common ground species of the area is a loess-like clay loam. There are sands observed near the river bed of Vorskla and clay on steep slopes. Soddy-meadow and chernozem-meadow, sandy loam and clay loam soils are involved in the bottomland forests formation. Typical chernozem occupies significant territories, which is formed by herbaceous grouping of mesoxerophytes, euxerophytes and xeromesophytes. Floodplain soils are divided into three parts: riverine, central and terrace near flood plain. In the riverine part is formed the most light mechanical components of interbedding soils formed on new derived silt from slightly humic layers. There are a low percent of humus (not more than 1 %) and nutritional chemicals. Thereby their fertility is low. In the central part of floodplain had been formed the sandy loam and clay loam soils with stronger profile on the massive, often calcareous or carbonaceous parent rock material. In cases of flood the water is widely overflowed and stay for a long time rich in sludge particles. It is the richest soils of the floodplain. The done research gave us the opportunity to clear up that the bottomland forests with short-term flooding of Poltava-city green belt are consist mainly of oak, aspen and alder forests. The formation and distribution of the main associations of floodplain forests depend on the regime of floodplain, trophotop and relief inhom*ogenuity. It was noticed that it can be found three more typical natural forest vegetations related to bottomland forests with short-term flooding inside the Poltava-city green belt: Dc' 3 (moist linden oak forest with hairlike sedge), Dn / 4 (alder forest with muddy tall herbaceous vegetation), Dc / 2 (live aspen forest with). It was noticed, that in all investigated plant formations the forest site type is sandy loam with different variations: live (SP / 2), moist (SP / 3), muddy (SP / 4). Different variations of soil has been investigated. There is no carbonate in soils of the investigated biogeocenosis. Water extract analysis tell about the lack of salinity properties, dry particles ranges (0,05–0,2 %), pH is alkaline. Detailed soil and geobotanical characteristics and establishing peculiarities of bottomland forests with short-term flooding adaphotop will give opportunity to reconstruct the existing Poltava-city green belt plantations and organize the stationary investigations with the aim of their more rational employment and saving.

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Tropical sandy beaches provide essential ecosystem services and support many local economies. In recent times, however, there has been a massive infrastructure expansion in popular tourist destinations worldwide. To investigate the shoreline variability at a popular tourist destination in Mexico, we used the novel semi-automatic CoastSat program (1980 to 2020) and the climate dataset ERA5 (wave energy and direction). We also measured the beach cross-shore distance and the foredune height with topographic surveys. The results indicate that the section of real estate seafront infrastructure in the study site presents a considerable shoreline erosion due to the fragmentation between the foredune ridge and the beach berm, based on the in situ transects. Moreover, foredune corridors with cross-shore distances of up to 70 to 90 m and dune heights of 8 m, can be seen in the short unobstructed passages between buildings. In the south section we found the coastline in a much more stable condition because this area has not had coastal infrastructures, as of yet. For the most part, the remote sensing analysis indicates constant erosion since 1990 in the real estate section (mainly seafront hotels) and an overall accretion pattern at the unobstructed beach-dune locations. This study demonstrates the catastrophic consequences of beach fragmentation due to unplanned real estate developments, by combining in situ surveys and a freely available big-data approach (CoastSat).

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Abstract The ChaoShan Depression is the largest Mesozoic depression covering an area of 3.7 x 104 km2 where the relict Mesozoic strata are up to 5000 m thick. It has experienced disruption since the late Mesozoic. In early survey, the oil-gas migration condition and reservoiring mechanism are poorly expounded from the Meso-Cenozoic tectonic superposition due to poor seismic imaging to the deep Mesozoic layers. New seismic surveys using long streamers and quasi three-dimensional layouts has improved obviously the deep images of the Mesozoic formations, enabling analysis of tectono-stratigraphic features and petroleum geology. Correlating to the regional Mesozoic stratigraphic and facies characteristics from the well LF35-1-1 and onshore outcrops, two sets of source layer tested with high organic carbon content are interpreted within the upper Triassic to mid-Jurassic semi-closed gulf sequences which become thicker toward the east side of Dongsha Island. Three sets of potential reservoir beds are also interpreted, which are a basin-floor fan sandstone layer of the Triassic-Jurassic boundary, a limestone layer atop the mid Jurassic, and a sandy layer in the Upper Jurassic. Over the low bulge of the ChaoShan Depression, a big anticline is found bounded by two sets of faults which played as migration passage for hydrocarbon from the deep Mesozoic source to the reservoir layers. Likely, one set of the fault act reverse barrier to block the petroleum escape, thus form the fault-bounded trap, favorable for future exploration.

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Soil was sampled according to the distance surrounding different activities area and on different levels of travel channel around the gold saddle tourist spots of Xilamuren grassland in Inner Mongolia. Soil samples were collected every 5 cm until down to 30cm in each plot with soil wreath knife. Analyze soil compaction, bulk density, soil moisture content, pH, soil organic matter, available P, total N, total P and total K by experiment. Through data analysis, study the response of tourism interference on soil physical and chemical properties. Study shows that the destruction of tourism activities on the grassland soil is big and the intensity of tourism activities are positively correlated to the degree of interference. The nearer to the concentrated region of tourism spots facilities, the greater intensity of tourist disturbance and the greater damage of soil. The damage of soil in south side was significantly greater than that in the north side. Travel interference changes differently in different tourism activity area. The damage extent of interference in obo district and bok field was greater than that on both sides of horse tract. Different levels of travel channel showed that interference degree was different by the frequency size of vehicle rolling and the destruction of soil conditions was consistent with it. Tourism interference is relatively concentrated. It destructs the local environment. As long as the tourism point, tourism activity area, the layout of tourism road should not be spread too disperse and messy, the impact of grassland landscape pattern will be significantly reduced, and the deterioration trend of ecological environment is expected to be controlled. Through analysis of different type of tourism activities zone, basic cover all aspects of the impact of grassland tourism development on grassland environment. The changes of grassland soil could be explained driven by tourism disturbance. It can provide alternative methods for tourism interference study and provide guidance for the management of grassland tourist areas. Grassland tourist spots tend to be concentrated in the excellent area of pasture landscape resources and environment, but also the fragile area in ecological environment. The interference of human activities are extremely sensitive whether in a desert steppe zone of brown soil as matrix soil or in typical grassland zone of chestnut soil as matrix soil, and even in the meadow steppe of chernozem as matrix soil. Once vegetation is destructed, soil has been the strength trampling, sandy desertification would grow rapidly. It would not only affect pasture tourism, but also would threaten the neighboring regions. Therefore, it is necessary to study the effect of tourism interference on the soil of grassland tourist spots.

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Between the diverse units geomorphologicals of the Bahia, are presents also the coastal plains and the coastal trays. Following to present line of beach, healthy noticed by its sandy forms, with colorings hom*ogeneous. Diverse works exist about the genesis litologics of those geomorphological rooms. It researches of big relevance published in national scope as the of Suguio (1975), Martin (1976) and Dominguez (1980) attribute of unanimous form the genesis of the present coastal plain and trays to the interactions between the erosive forces of the sea and depositional conditions on the part of the continental rivers. The objective of that work was map the Coastal Plain and the Coastal Tray in the stretch between Ilhéus and Olivença, and discuss about the activities of use of him soil that grant hidrographics impacts and partner-environmental about both. It was carried out the mapping in scale of detail (1:5.000) of the coastal plain utilizing image IKONUS high-resolution. The corresponding zone to the plain at present is utilized in diverse typologies of use of him soil, since cultivations to property lots. The friable texture of the substrate implies in a sensibility the antropological interventions in the same one. The deforestation in the trays, the urban growth, the extraction of sand and the absence of specific plannings for those rooms geomorphologicals are the present causes of hidrographics degradation and partner-environmental problems to same. The intention of that work is going to dispose facts for contribute with better planning in the area of study

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Introduction: Lesser weever fish are saltwater fish that are found on the Mediterranean and European coasts, over sandy and muddy seabed areas, typically around the summer season. These bottom dwellers have envenoming dorsal spines that sting when stepped on. Severe pain is the main symptom. Initial treatment involves wound irrigation, removal of spines if they are visible and immediate hot water immersion (HWI). Tetanus prophylaxis, leg elevation and analgesia are recommended after pain subsides. HWI treatment is described as immersion of the affected area in hot, but not scalding, water to tolerance (upper limit 45 °C) for 30–90 min or until there is significant pain relief. While HWI is an effective therapy for the pain control of marine envenomation, it presents a potential risk of thermal burn injury in the untrained or unsupervised. Here, we present a case of an iatrogenic thermal burn after HWI for the treatment of a weever fish sting. Case report: A 16-year-old girl was referred to our outpatient department with a superficial dermal thickness burn to her big toe 12 days after accidental stepping on a lesser weever fish. She reported receiving HWI treatment at the scene of the injury. She was treated with dressing, oral antibiotics and leg elevation. This healed with no sequalae at nine-month follow-up. Conclusion: Thermal burn injury can occur after HWI treatment. Providers should be aware and diligent while the patient needs to be educated in the potential risks. Lay Abstract 5, e, s Stings from lesser weever fish occur mostly in the summer months. These bottom dweller saltwater fish are found in the Mediterranean and European coasts, over sandy and muddy seabed areas; it releases venom from its dorsal spine when stepped on. Severe pain is the main symptom. Recommended first aid includes wound irrigation, removal of spines if they are visible and immediate hot water immersion (HWI) treatment. HWI means immersion of the affected part into hot, but not scalding, water (upper limit 45 °C) for 30–90 min or until pain is alleviated. In an ideal situation, the water temperature should be checked with a thermometer. However, in practice, where no thermometer is available, the water must be tested before immersion. It is advised to ensure that the water should be no hotter than the first aider can stand or the highest temperature tolerable by the patient. However, HWI treatment has a potential risk of burn injury. Here we describe a case of a 16-year-old patient who sustained burn injury after HWI therapy received after a sting by a weever fish. The patient was treated with dressings and the wound healed without requiring surgical intervention. Here, we like to highlight that although HWI is effective in treating stings from marine animals, both the provider and the patient need to be aware of potential burn injury associated with this treatment.

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To better manage southern Ontario's natural forests, the former and present status of old growth must be understood. We hypothesize that old-growth pine (Pinus spp.), although dominant elsewhere, was less common in southern Ontario than popular history suggests: we are obliged to evaluate historical information that has been filtered both by the original compilers and through our own biases. Beginning around 600 AD, the predominant beech (fa*gus americana) forest was partially replaced by maple (primarily Acer saccharum), oaks (Quercus spp.) and eastern white pine (P. strobus). This pine increase either followed abandonment of pre-Columbian agriculture or, more plausibly, accompanied climate cooling. Eighteenth and 19th century European settlers encountered abundant large trees, which they hewed for square pine timber, milled timber, and tanbark. Other stands were cut and burned for agricultural clearance, with a potash by-product. Until recently, Ontario research emphasized the old-growth pine stands of central and northern Ontario to the relative exclusion of other kinds of old forest because very few southern Ontario old-growth stands remained to study. Ontario forest resource inventory data (FRI) show stands of over 150 years totalling only 1475 ha in 1978, concentrated on the Oak Ridges Moraine, the St. Lawrence Valley and the Awenda Peninsula. Red (P. resinosa) and eastern white pine stands constituted only 5.3% of the 1978 forested area, with virtually none of over 150 years, whereas eastern hemlock (Tsuga canadensis) stands constituted 12.8%. The difficulty in finding modern old growth necessitates historical reconstruction using physical, written and graphical resources, including early survey records and trade statistics. In a case study of 1822 survey data from Darling Township (Lanark Co.) and 1960 FRI, vegetation was classified using TWINSPAN and mapped using ARC/INFO Thiessen polygons. In 1822, dominant hemlock occupied half the township but it has since been eliminated as a dominant. Conversely, there were no pine-dominated forests in 1822, but these had increased to 16% of the area by 1960. A second case used similar methods, with 1855 data for St. Edmunds and Lindsay townships (Bruce Co.) and 1981 FRI. Although logging halved the area and reduced the stature of pines in the large pinery, the elimination of dominant hemlock (originally 41% by area) is more significant. Fragmentary square timber trade data suggest that at least half the large pines in Bruce County were in St. Edmunds, so pine must have been spectacularly concentrated in a few areas. The third case, a map constructed from Gourlay's 1817–1819 survey, also demonstrates that pine-dominated areas were in the minority in southern Ontario, concentrated on sandy soils around Lakes Ontario and Erie. However, big hemlocks, beeches, maples and oaks were much more common overall. Management responses to this information should include designation of older southern Ontario forest stands (especially those never cleared since settlement) for maturation into an old-growth state, and the systematic restoration of eastern hemlock and beech stands for conservation purposes in southern Ontario. Key words: old-growth forest, Canada, Ontario, historical ecology, forest history

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ABSTRAK<br />Salah satu permasalahan dalam budidaya jahe (Zingiber officinale<br />L.) adalah masih rendahnya produktivitas dan mutu jahe, yang antara lain<br />disebabkan oleh penggunaan bahan tanaman/benih yang masih asalan/<br />kurang memenuhi persyaratan. Usaha untuk penyediaan benih yang<br />bermutu di antaranya dapat dilakukan dengan penanaman di daerah yang<br />tepat serta menyimpan benih dengan cara yang baik dan benar. Sampai<br />saat ini informasi mengenai mutu benih jahe dari lokasi produksi<br />(ketinggian tempat, jenis lahan dan jenis tanah) yang berbeda masih<br />terbatas. Oleh karena itu, percobaan ini dilakukan dengan tujuan untuk<br />mempelajari mutu fisik dan fisiologik benih jahe dari lokasi produksi<br />yang berbeda selama periode penyimpanan. Percobaan dilakukan di daerah<br />sentra produksi jahe di Dusun Cipanas, Desa Werasari, Kecamatan<br />Bantarujek, Kabupaten Majalengka, Jawa Barat dari bulan Juli sampai<br />November 2003, dengan menggunakan tiga jenis jahe yaitu: Jahe Putih<br />Besar/JPB (Z. officinale var. officinale), Jahe Putih Kecil /JPK (Z.<br />officinale var. amarum), dan Jahe Merah/JM (Z. officinale var. rubrum).<br />Untuk masing-masing jenis jahe diperlakukan dengan kombinasi lokasi<br />produksi dan lama penyimpanan. Untuk masing-masing jenis jahe<br />percobaan disusun dalam rancangan petak terbagi (RPT) dengan tiga<br />ulangan. Petak utama yaitu asal lokasi produksi benih: (1) Cipanas<br />lingkungan tumbuh dengan tinggi tempat ± 600 m dpl, lahan sawah tadah<br />hujan, tekstur tanah liat berpasir, kemiringan 0-10% dan (2). Cipicung<br />lingkungan tumbuh dengan tinggi tempat ± 800 m dpl, lahan tegalan,<br />tekstur tanah debu berpasir, kemiringan 10-20%. Anak petak yaitu periode<br />penyimpanan : 0, 1, 2, dan 3 bulan. Parameter yang diamati meliputi kadar<br />air benih, penyusutan bobot benih dan daya tumbuh benih. Hasil<br />penelitian menunjukkan bahwa untuk masing-masing jenis jahe (JPB,<br />JPK, dan JM) yang berasal dari Cipanas maupun Cipicung, mempunyai<br />mutu fisik (kadar air dan penyusutan bobot rimpang) tidak nyata<br />dipengaruhi oleh interaksi lokasi produksi dan lama penyimpanan, serta<br />faktor tunggal lokasi produksi, tetapi nyata dipengaruhi oleh faktor<br />tunggal lama penyimpanan Setelah tiga bulan penyimpanan kadar air<br />benih rimpang dari lokasi produksi Cipanas dan Cipicung untuk JPB masih<br />82,43% dan 80,67%, JPK kadar airnya masih 84,16% dan 81,31%, dan<br />JM 69,49% dan 65,88%. Penyusutan bobot rimpang untuk masing-masing<br />jenis jahe dari lokasi produksi Cipanas dan Cipicung sebagai berikut : JPB<br />14,44% dan 14,82% ; JPK 17,84% dan 26,11% ; JM 48,40% dan 37 14%.<br />Daya tumbuh benih setelah 3 bulan penyimpanan untuk masing-masing<br />jenis jahe dari lokasi produksi Cipanas dan Cipicung sebagai berikut : JPB<br />92,00- 93,32%, JPK 85,33- 86,67% dan JM 86,67-89,33%. Kadar air<br />benih/rimpang jahe menurun, sedangkan penyusutan bobot rimpang<br />meningkat sejalan dengan lamanya penyimpanan. JPB, JPK dan JM yang<br />berasal dari Cipanas maupun Cipicung dapat disimpan selama tiga bulan,<br />tanpa mengalami penurunan mutu fisik dan fisiologik yang berarti.<br />Kata kunci : Zingiber officinale, lokasi produksi benih, lama<br />penyimpanan, mutu benih<br />ABSTRACT<br />Production effect of locations and storage periods on<br />ginger seeds quality<br />Problems of ginger cultivation are low productivity and quality of<br />ginger due to low quality of ginger seed for planting materials. High<br />quality of ginger seed will be achieved by planting ginger seed in suitable<br />place and methods. Recently, the information concerning the quality of<br />ginger seed from different production location (altitude, soil types and<br />area) is still limited. Based on the problems, this experiment was<br />conducted with special aim to study the physical and physiological quality<br />of ginger seed from different sources of seed during storage periods. The<br />experiment was conducted at the producer center i.e. of ginger, Cipanas,<br />Werasari Village, Sub District Bantarujek, District Majalengka, from July<br />to November, 2003. The experiment used three kinds of ginger namely<br />was white big ginger (Z. officinale var. officinale), small white ginger (Z.<br />officinale var. amarum) and red ginger (Z. officinale var. rubrum). The<br />experiment was arranged in split-plot design with 3 replications. The main<br />factor was two productions location, there were: ginger seed produced in<br />Cipanas (altitude ± 600m above sea level, rain fed area, clay sandy, and<br />slope 0-10%) and ginger seed produce in Cipicung (altitude ± 800m above<br />sea level, upland area, clay sandy, and slope 10 -20%). The sub plot were<br />0, 1, 2 and 3 month periods of storage. Variables were observed include<br />moisture content, weight and germination percentage of ginger<br />seed/rhizome after three months storage. The results of experiment<br />indicated that for each kind of ginger (white big ginger, white small ginger<br />and red ginger) physical quality (moisture content of seeds and loosing<br />weight of seed) had no significant interaction between location production<br />and period of storage or single factor of location production. However,<br />they were significantly effected by single factor periods of storage. After 3<br />months storage, the moisture content of white big ginger produced from<br />Cipanas were 82,43% and 80,67%. For white small ginger the moisture<br />contend were 84,16% and 81,31%, especially white small ginger produced<br />from Cipanas and Cipicung. While the moisture content of red ginger seed<br />produced from Cipanas and Cipicung were 69,47% and 63,88%. Weight<br />decrease for each kinds of ginger produced from Cipanas and Cipicung<br />were as follows white big ginger 14,44% and 14,82%, white small ginger<br />17,84% and 26,11%, red ginger 48,40% and 37,14%. After 3 months<br />storage the germination percentage for each kind of ginger produced from<br />Cipanas and Cipicung were as follows white big ginger 92,00% and<br />93,32%, white small ginger 86,67% and 83,33% and red ginger 89,33%<br />and 86,67%.<br />Key words : Zingiber officinale, location of seed production, storage<br />periods, seed quality

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Abstract. A shallow-water area in the Santa Barbara Channel, California, known collectively as the Coal Oil Point seep field, is one of the largest natural submarine hydrocarbon emission areas in the world. Both gas and oil are seeping constantly through a predominantly sandy seabed into the ocean. This study focused on the methanotrophic activity within the surface sediments (0–15 cm) of the permeable seabed in the so-called Brian Seep area at a water depth of ∼10 m. Detailed investigations of the sediment biogeochemistry of active gas vents indicated that it is driven by fast advective transport of water through the sands, resulting in a deep penetration of oxidants (oxygen, sulfate). Maxima of microbial methane consumption were found at the sediment-water interface and in deeper layers of the sediment, representing either aerobic or anaerobic oxidation of methane, respectively. Methane consumption was relatively low (0.6–8.7 mmol m−2 d-1) in comparison to gas hydrate-bearing fine-grained sediments on the continental shelf. The low rates and the observation of free gas migrating through permeable coastal sediments indicate that a substantial proportion of methane can escape the microbial methane filter in coastal sediments.

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In recent years, satellite imagery has shown its potential to support the sustainable management of land, water, and natural resources. In particular, it can provide key information about the properties and behavior of sandy beaches and the surrounding vegetation, improving the ecomorphological understanding and modeling of coastal dynamics. Although satellite image processing usually demands high memory and computational resources, free online platforms such as Google Earth Engine (GEE) have recently enabled their users to leverage cloud-based tools and handle big satellite data. In this technical note, we describe an algorithm to classify the coastal land cover and retrieve relevant information from Sentinel-2 and Landsat image collections at specific times or in a multitemporal way: the extent of the beach and vegetation strips, the statistics of the grass cover, and the position of the shoreline and the vegetation–sand interface. Furthermore, we validate the algorithm through both quantitative and qualitative methods, demonstrating the goodness of the derived classification (accuracy of approximately 90%) and showing some examples about the use of the algorithm’s output to study coastal physical and ecological dynamics. Finally, we discuss the algorithm’s limitations and potentialities in light of its scaling for global analyses.

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Abstract. Equatorial podzols are soils characterized by thick sandy horizons overlying more clayey horizons. Organic matter produced in the topsoil is transferred in depth through the sandy horizons and accumulate at the transition, at a depth varying from 1 to more than 3 m, forming deep horizons rich in organic matter (Bh horizons). Although they cover great surfaces in the equatorial zone, these soils are still poorly known. Studying podzols from Amazonia, we found out that the deep Bh horizons in poorly drained podzol areas have a thickness higher than 1 m and store unexpected amounts of carbon. The average for the studied area was 66.7 ± 5.8 kgC m−2 for the deep Bh and 86.8 ± 7.1 kgC m−2 for the whole profile. Extrapolating to the podzol areas of the whole Amazonian basin has been possible thanks to digital maps, giving an order of magnitude around 13.6 ± 1.1 PgC, at least 12.3 PgC higher than previous estimates. This assessment should be refined by additional investigations, not only in Amazonia but in all equatorial areas where podzols have been identified. Because of the lack of knowledge on the quality and behaviour of the podzol organic matter, the question of the feedback between the climate and the equatorial podzol carbon cycle is open.

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<p><strong>Abstract.</strong> For a long time <i>Lençóis Maranhenses</i> region in Northeastern Brazil, has been calling attention for being an area of extreme contrasts, not only under the physical-geographical and climatic point-of-view, but also because of the great contradictions and social conflicts that can be found there. A big part of the territory has been officially declared a National Park on June 2nd, 1981 (BRASIL, 1981), although the Region of <i>Lençóis</i> and <i>Pequenos Lençóis</i> (Little Lençóis) extends beyond the area protected by the National Park (TSUJI, 2002). Communities established inside the National Park are supplied with electricity, while others, just a few kilometres away; lack this resource, even being located within the official perimeter (SOUZA, 2007). The consequences of these expressions of spatial injustice can be considered terrible: severe health problems, serious conflicts between tourism activities and the traditional ways of production, among others.</p><p> The region (Figure 1) has never been object of a multidisciplinary and organized study in the form of an atlas, in spite of being very popular and attractive under the touristic point-of-view. For this reason, the research intends to elaborate the Social-Environmental Atlas of <i>Lençóis Maranhenses</i> in its wholeness, and, in a later stage, proceed with its publication in paper and digital form. This atlas will have about 200 pages and, initially, 13 sections have been defined. In view of its thematic and territorial content, it can be classified in the category of special regional atlas (SALITCHEV, 1979).</p><p> Therefore, the proposed atlas will focus not only on the National Park but also on its surroundings. Thus, we intend to study all the geographical space, categories of land use and forms of occupation by society as a whole, with emphasis on the traditional communities which dwell in the area. This region is characterized by an environment unfit for most farming crops, not only because of its sandy soil, but also because of moving dunes and of the hydric regime, sometimes with rain in excess, other times with long drought periods (Figure 2). All these factors, associated to the difficult access to the area, contribute to a most vulnerable population, causing an obvious influence on their ways of life. Nevertheless, people who live there have found ways to produce and provide for themselves. Fishing and fruit collecting, vegetal fibres and other natural products are among the usual sustenance activities. Many turn to breed small herds of goat, sheep and cattle, or work little parcels of land; they may also devote themselves to craftsmanship and various activities related directly or indirectly to tourism. Therefore, we feel that the use of the methodology called Cybercartography (TAYLOR AND LAURIAULT, 2014) will help us to understand the flows and habits in this region, thus contributing to improve the life quality of local communities.</p><p> Even if this location is known virtually since the beginning of European occupation, and there exists a National Park established by law in 1981 (BRASIL, 1981), up to this moment there has never been an atlas devoted exclusively to this part of the state of Maranhão. This is, therefore, the first scientific challenge: to create, compile and present maps and texts specifically dedicated to Lençóis Maranhenses, and organized in form of a special regional atlas, showing the socio-environmental dynamics of the place.</p><p> Moreover, there is the issue of employing techniques of Cybercartography, specifically of the Nunaliit Cybercartography Atlas Framework (TAYLOR e CAQUARD, 2006). We intend to use this technological platform, designed to create apps of interactive mapping in the internet, using different sources of data and multimedia, which allow users a high degree of participation. By default, the Nunaliit Framework employs a simple and flexible database, founded on documents to store any graphic objects or descriptive attributes (texts). As it happens, virtually in all the directly affected area, and of interest for the atlas project, the regular access to Internet is much reduced or virtually inexistent, even if considering the mobile phone nets.</p><p> For this reason, the atlas will be devised in simultaneous versions: a traditional one, in paper print, and also a complementary version created in the Framework for Cybercartographic Atlas. Moreover, the team that developed the Nunaliit platform, led by Professor Fraser Taylor, from the Department of Geography and Environmental Studies and Director of Research Center in Geomatics and Cartography of Carleton University in Ottawa, Canada, has kindly offered to collaborate in this project, supporting the creation of the cybercartographic version, also developing specific apps that allow the elaboration of maps in PDF off-line, which will be then incorporated to the framework of the traditional printed version.</p><p> We believe that the availability of the digital version (Cybercartographic) of the Atlas of Lençóis Maranhenses will definitely contribute to the digital inclusion of local communities. With the results reached by this project, we understand that it will be possible to know better the distribution of the communities in the region, their kinds of use and means of production, with emphasis on the handling of natural resources and cultural aspects. Thus, with a better knowledge about the actors in the territory, it is intended to stimulate regional and local actions with respect to environmental education and initiatives of social inclusion.</p><p> Therefore, and important objective is to divulge the work and methodology proposed, to incorporate and encourage participation not only of the academic-scientific sector, but also of managers and local population, especially those who live within Lençóis Maranhenses and its area of influence. Thus, this methodological research may be applied to other places in Brazil, for example, with indigenous population, communities of “<i>quilombolas</i>” (descendants of former slaves), “<i>caiçaras</i>” (sea shoreline population) and others.</p>

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Lots of loess sediments, mostly located at the Eastern Songnen Plain, have been deposited through the whole Quaternary period. In order to determine their sources, samples were collected from a number of representative areas, such as the dust loess, river sediment of the Songhua River and the Horqin sandy land. Heavy mineral assemblage analysis of these samples shows that the dust samples share a consistent character, which is similar to the Songhua Rivers sediments. In contrast, there is a big difference between the dust samples and the Horqin. Heavy minerals assemblage from Eastern Songnen Plain dust loess compatible with a dominant source in the nearby river sediments and the weathered granitoid of the Songhua River drainage basin, such as the Hinggan Mountains and Eastern mountains, with additional minor contributions from the Horqin sandy land or the distal dust source.

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The work presents a sequel of publication series on vegetation of the Dnieper River mouth region. The characteristic of syntaxonomical diversity of forest and shrub vegetation of the Dnieper River mouth area belonging to the Salicetea purpureae and Alnetea glutinosae classes are presented. There have been picked out 12 associations and 1 community attributed to 3 orders and 4 alliances. Salicetea purpureae class in the Dnieper River mouth is represented by communities formed under long time inundation conditions, along the sides of islands, arms of the main river-bed, lakes, and also along the sides of secondary arms with salty marsh or soddy sandy soils. These communities are more typical for river mouth habitats. The class includes the Salicetum albae, Saliceto-Populetum, Populetum nigro-albae, Fraxino-Populetum, Populetum marylandicae, Elaeagnetum angustifoliae, Amorpha fruticosa com., Salicetum triandrae aassociations. Mass expansion of com. Amorpha fruticosa was recorded in the Dnieper River Delta. Due to the high coenotic activities of this species the community spreads over the flood territories. To prevent Amorpha fruticosa invasions there have been induction of a long time and powerful spring water discharge from the reservoirs of the Dnieper’s cascade. Alnetea glutinosae class includes Salicetum cinereae, Thelypteridi-Salicetum cinereae, Urtico dioicae–Alnetum glutinosae, Carici acutiformis–Alnetum, Carici elatae–Alnetum glutinosae associations. The plant communities occur in the nature complexes of the river mouth at the offshore parts of islands under a long time inundation. Syntaxonomical analysis of phytocoenotic tables confirms the integration of Alnetea glutinosae and Franguletea classes as long as these communities occupy similar habitats (mire ecotopes with peaty-mire and mire soils) and they have a number of common diagnostic species. The coenotaxonomical and coenotical particularities of forest and shrub vegetation communities were revealed. In comparison with similar plant communities of the northern regions they do not take a big part in specific composition of boreal flora, but the role of species of the ancient Mediterranean origin is more remarkable. Considerable part of alnetal florocoenotic complex species is absent (Kuzmichev, 1992) or so-called alder forest historical suite (Zozulin, 1973), in particular, genus Sphagnum species. Other representatives of mire flora that are typical for mezotrophic and eutrophic mires of the forest zone are missing also. The forest stand structure is characterized by slight or absent understory, and in grass layer there are typical steppe and salt habitat species. As a result of significant human impact for the last ten years an expansion of mesophytes and xeromesophytes in the grass layer as well as adventitious and ruderal plant species was noticed. A change of coenoses of flood-forest vegetation under recreation by the communities of forest-park type takes place, and in depressions they are replaced by mire or salt meadows (Chinkina, 2003). It is necessary to underline the needs of ecology-sozological monitoring of their conditions and conservation of coenoses as well as the rare species population.

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Ground penetrating radar (GPR) was used in several selected deltaic sedimentary environments to better understand subsurface stratigraphy and reconstruct former depositional environments. The profiles provide high-resolution, continuous subsurface data on facies thickness and depths, orientation of major sedimentary structures, postdepositional failure planes, and depth of peat deposits.Field experiments were carried out on six river deltas. Records from four of the deltas exhibit sedimentary facies; a record from one delta shows a possible slump; and records from another delta reveal the thickness and stratigraphic relationships of peat deposits. The delta types are (i) sandy, wave influenced; (ii) sandy, immature wave influenced (steeper middle and lower shoreface); (iii) sandy braided; and (iv) gravelly, fan–foreset.In areas of limited subsurface control (stratigraphic logs from drill core, cutbank exposure, or geophysical logs), radar profiles can provide ''big picture'' perspectives of the subsurface, a view only available in laterally extensive exposures. High-resolution profiles of subsurface stratigraphy and sedimentary facies from GPR provide an opportunity for geomorphologists and sedimentologists to further advance field research. Although GPR has limited success in silt and clay, results from sand and gravel deposits often reveal detailed facies assemblages.

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Phosphorus fractions were determined in soil samples from areas fertilized or not with farmyard cattle manure (FYM) and in samples of FYM used in the semi-arid region of Paraiba state, Brazil. Soil samples were taken from the 0-20; 20-40 and 40-60 cm layers of 18 cultivated areas, which, according to interviews with farmers, had been treated with 12 to 20 t ha-1 FYM annually, for the past 2 to 40 years. Soil samples were also collected from four unfertilized pasture areas as controls. Phosphorus in the soil samples was sequentially extracted with water (Pw), resin (Pres), NaHCO3 (Pi bic and Po bic), NaOH (Pi hid and Po hid), H2SO4 (Pacid) and, finally, by digestion with H2SO4/H2O2 (Presd). Nine FYM samples were extracted with water, resin, Mehlich-1, H2SO4, NaOH or digestion with H2SO4/H2O2, not sequentially, and the extracts analyzed for P. The sampled areas had hom*ogeneous, sandy and P-deficient soils; increases in total soil P (Pt) above the mean value of the control areas (up to 274 mg kg-1 in the 0-20 cm layer of the most P-enriched samples) were therefore attributed to FYM applications, which was the only external P input in the region. Regression analysis was used to study the relationship between soil P fractions and Pt. The Pacid fraction, related to Ca-P forms, showed the greatest increases (p < 0.01) as a result of FYM applications, rising from 8.4 mg kg-1 in a non-fertilized sample to 43.8 mg kg-1 in the sample with the highest Pt content. The sum of Pw, Pres and Pi bic, considered as labile P, showed comparable increases with Pacid, while Pi hid showed the smallest increase due to FYM applications. Organic P forms also increased, more so the fraction Po hid, considered less labile, than the more labile one, Po bic. The residual P fraction was practically half of Pt, independently of the Pt value. Increases in labile P, Pacid and organic P were justified by the high average concentration of Pw (36 %), Pacid (34 %), and Po hid (30 %) in the FYM. Significant changes in the proportion of P forms among soil layers indicated the downward movement of P in organic forms.

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Based on "controlling sand to fix sand, managing sand with sand", aiming to the problems of sand hazard in the northwest desert area during the highway construction, the new technique of sand fixation is formed by bags of using widely distributed desert aeolian sand. The flow field characteristics of aeolian sand barrier with fins & nofins are analyzed by wind tunnel tests, the influence of sand barrier forms and specifications to wind speed reduction ratio and roughness are researched by field tests as well as sand fixation effect, the results can provide the guidance and application value to sand fixation engineer of the desert areas

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Spodosol soil of Typic Placorthod sub-group of East Barito District is one of the problem soils with the presence of hardpan layer, low fertility, low water holding capacity, acid reaction and it is not suitable for oil palm cultivation without any properly specific management of land preparation and implemented best agronomic practices. A study was carried out to evaluate the soil characteristic of a big hole (A profile) and no big hole (B profile) system and comparative oil palm productivity among two planting systems. This study was conducted in Spodosol soil at oil palm plantation (coordinate X = 0281843 and Y = 9764116), East Barito District, Central Kalimantan Province on February 2014, by surveying of placic and ortstein depth and observing soil texture and chemical properties of 2 (two) oil palm's soil profiles that have been planted in five years. Big hole system of commercial oil palm field planting on the Spodosol soil area was designed for the specific purpose of minimizing the potential of a negative effect of shallow effective planting depth for oil palms growing due to the hardpan layer (placic and ortstein) presence as deep as 0.25 - 0.50 m. The big hole system is a planting hole type which was vertical-sided with 2.00 m x 1.50 m on top and bottom side and 3.00 m depth meanwhile the 2:1 drain was vertical-sided also with 1.50 m depth and 300 m length. Oil palm production was recorded from the year 2012 up to 2014. Results indicated that the fractions both big hole profile (A profile) and no big hole profile (B profile) were dominated by sands ranged from 60% to 92% and the highest sands content of non-big hole soil profile were found in A and E horizons (92%). Better distribution of sand and clay fractions content in between layers of big hole soil profiles of A profile sample is more uniform compared to the B profile sample. The mechanical holing and material mixing of soil materials of A soil profile among the upper and lower horizons i.e. A, E, B and C horizons before planting that resulted a better distribution of both soil texture (sands and clay) and chemical properties such as acidity value (pH), C-organic, N, C/N ratio, CEC, P-available and Exchangeable Bases. Investigation showed that exchangeable cations (Ca, Mg, K), were very low in soil layers (A profile) and horizons (B profile) investigated. The low exchangeable cations due to highly leached of bases to the lower layers and horizons. Besides, the palm which was planted on the big hole system showed good adaptation and response positively by growing well of tertiary and quaternary roots that the roots were penetrable into deeper rooting zone as much as >1.00 m depth. The roots can grow well and penetrate much deeper in A profile compared to the undisturbed hardpan layer (B profile). The FFB (fresh fruit bunches) production of the non-big hole block was higher than the big hole block for the first three years of production. This might be due to the high variation of monthly rainfall in-between years of observation from 2009 to 2014. Therefore, the hardness of placic and ortstein as unpenetrable agents by roots and water to prevent water loss and retain the water in the rhizosphere especially in the drier weather. In the high rainfall condition, the 2:1 drain to prevent water saturation in the oil palm rhizosphere by moving some water into the drain. Meanwhile, the disturbed soil horizon (big hole area) was drier than un disturbance immediately due to water removal to deeper layers. We concluded that both big hole and 2:1 drain are a suitable technology for Spodosol soil land especially in preparing palms planting to minimize the negative effect of the hardpan layer for oil palm growth.

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Abstract. Composite agricultural systems with permanent maize cultivation in the uplands and irrigated rice in the valleys are very common in mountainous southeast Asia. The soil loss and fertility decline of the upland fields is well documented, but little is known about reallocation of these sediments within the landscape. In this study, a turbidity-based linear mixed model was used to quantify sediment inputs, from surface reservoir irrigation water and from direct overland flow, into a paddy area of 13 ha. Simultaneously, the sediment load exported from the rice fields was determined. Mid-infrared spectroscopy was applied to analyze sediment particle size. Our results showed that per year, 64 Mg ha−1 of sediments were imported into paddy fields, of which around 75 % were delivered by irrigation water and the remainder by direct overland flow during rainfall events. Overland flow contributed one-third of the received sandy fraction, while irrigated sediments were predominantly silty. Overall, rice fields were a net sink for sediments, trapping 28 Mg ha−1 a−1 or almost half of total sediment inputs. As paddy outflow consisted almost exclusively of silt- and clay-sized material, 24 Mg ha−1 a−1 of the trapped amount of sediment was estimated to be sandy. Under continued intensive upland maize cultivation, such a sustained input of coarse material could jeopardize paddy soil fertility, puddling capacity and ultimately food security of the inhabitants of these mountainous areas. Preventing direct overland flow from entering the paddy fields, however, could reduce sand inputs by up to 34 %.

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The approaches to the use of catena method of studying the diversity of soil animal communities’ arena landscape of the Dnieper River Valley (within the natural reserve “Dnieper-Orelsky” using phytoindication estimation have been developed in the present article. Soil animals ecomorphes have been verified on the basis of main trends variability of environmental conditions which evaluated by means of phytoindication approaches. Monitoring polygon situated in the north-eastern part of the natural reserve "Dnieper-Orelsky". The width of the polygon is 3260 m, height – 2850 m, its total area is 930 hectares. Inside the polygon we selected some five plots: on the slope of the sand dunes at the border the sandy steppe and Acer tataricum shrub; on the slope of the Northern exposure of the Orlova valley in Acer tataricum oak forest with Dáctylis glomeráta; in terrace near the flood plain on the border with the lower part of the slope, in elm-black poplar forest with Glechóma hederácea; in the waterlogged tributary of river Protoch on the border of the marsh and forest ecosystems; in river Protoch in grass community, in a gradient from the marsh community to steppe meadows. Each plot was represented by 105 squares of size 3×3 m. Squares arranged in 7 contiguous rows of 15 squares in each. Plot size was 21×45 m. Big side plot was located along the visually discernible gradient terrain topography and vegetation cover. In each square we made a description of the vegetation with the assessment of the projective cover with a lag of 10%. In the center of each square we sampled soil of 0.25×0.25 m from which the soil macroinvertebrates have been extracted by hand sorting. The ordination of mesopedobionts communities has been applied to multidimensional scaling procedure based on metrics of Bray-Curtis with provisional data on transformation according to Hellinger. The phytoindication estimation of the environmental regimes have been found to be statistically significant predictors of multidimensional scales that obtained after ordination of mesopedobionts communities. Dimension 1 can be explained by edaphotop nutrient status, dimension 2 can be explained by edaphotop humidity, dimension 3 may be explained by soil aeration, dimension 4 may be explained by quantity of carbonates in soil. Dimensions 5 and 6 have a complex factor nature which is difficult to interpret meaningfully. Environmental assessment regimes using phyto-indicative scales enabled set the value of soil carbonate content and aeration in structuring of soil animals communities. The obtained result makes reasonable provision of new ecomorphes of soil animals such as aèromorph and carbonatomorph. Aèromorphes are ecological group that combines soil animals, preferring similar condition of soil aeration, among which are highlighted in aerophyles, sub-aerophyles, hemiaerofobes and subaerofobes. Carbonatomorphes are ecological group that combines soil animals, preferring similar condition of carbonates content in soil, among which are highlighted in carbonatofobes, akarbonatophyles, hemicarbonatophyles, carbonatophyles and hyper-carbonatophyles. Classic catena approach for biogeocenotic and landscape diversity investigation have been supplemented by the assessment of the ecological regimes through phytoindication and ecomorphic analysis of vegetation. Ordinates of ecological regimes are the gradients of variation of soil animal communities. Information and valuable markers of vegetation (phytoindication scale and ecomorphes) can be used as training variables to assess the indicator properties of soil animal communities. Ecomorphes of soil animals reflect the main aspects of the structural organization of their communities and may serve as valuable indicators of the properties and behaviors of soil as environment of living organisms.

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Abstract Continued failure of most insecticides for control of CPB in the Anoka Sand Plains growing area stimulated further comparisons of biologicals, inorganics, and synthetic materials for CPB management. Soils are sands at this location. Plots were established in an irrigated commercial potato field. The individual plot consisted of 4—25 ft rows with a row width of 3 ft. Treatments were arranged in a randomized complete block design and were replicated 4 times. The grower treated all of the field, including the plots, with Thiodan and Asana XL at 1.0 lb and 0.5 lb Al/acre respectively on 8 Jul and 16 Jul. Plot treatments were applied on 25 Jun, 6 and 19 Jul using a CO2 hand sprayer with about 20 gals total material/acre and 40 psi pressure. Larval ratings and defoliation estimates were taken on 6 and 19 Jul. Vines were killed on 3 Aug and yields collected on 18 Aug. The center 2 rows of each plot were harvested for yield.

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Abstract. Although patterns between plant diversity and ecosystem productivity have been much studied, a consistent relationship has not yet emerged. Differing patterns between plant diversity and productivity have been observed in response to spatial variability of environmental factors and vegetation composition. In this study, we measured vegetation cover, plant diversity, productivity, soil properties and site characteristics along an environmental gradient (mobile dune, semi-fixed dune, fixed dune, dry meadow, wet meadow and flood plain grasslands) of natural sandy grasslands in semiarid areas of northern China. We used multivariate analysis to examine the relationships between environmental factors, vegetation composition, plant diversity and productivity. We found a positive correlation between plant diversity and productivity. Vegetation composition aggregated by the ordination technique of non-metric multidimensional scaling had also a significantly positive correlation with plant diversity and productivity. Environmental gradients in relation to soil and topography affected the distribution patterns of vegetation composition, species diversity and productivity. However, environmental gradients were a better determinant of vegetation composition and productivity than of plant diversity. Structural equation modeling suggested that environmental factors determine vegetation composition, which in turn independently drives both plant diversity and productivity. Thus, the positive correlation between plant diversity and productivity is indirectly driven by vegetation composition, which is determined by environmental gradients in soil and topography.

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Abstract. The Tommeliten seepage area is part of the Greater Ekofisk area, which is situated above the Tommeliten Delta salt diapir in the central North Sea (56°29.90' N, 2°59.80' E, Norwegian Block 1/9, 75 m water depth). Here, cracks in a buried marl horizon allow methane to migrate into overlying clay-silt and sandy sediments. Hydroacoustic sediment echosounding showed several venting spots coinciding with the apex of marl domes where methane is released into the water column and potentially to the atmosphere. In the vicinity of the gas seeps, sea floor observations showed small mats of giant sulphide-oxidizing bacteria above patches of black sediments as well as carbonate crusts, which are exposed 10 to 50 cm above seafloor forming small reefs. These Methane-Derived Authigenic Carbonates (MDACs) contain 13C-depleted, archaeal lipids indicating previous gas seepage and AOM activity. High amounts of sn2-hydroxyarchaeol relative to archaeol and low abundances of biphytanes in the crusts give evidence that ANaerobic MEthane-oxidising archaea (ANME) of the phylogenetic cluster ANME-2 were the potential mediators of Anaerobic Oxidation of Methane (AOM) at the time of carbonate formation. Small pieces of MDACs were also found subsurface at about 1.7 m sediment depth, associated with the AOM zone. This zone is characterized by elevated AOM and Sulphate Reduction (SR) rates, increased concentrations of 13C-depleted tetraether derived biphytanes, and specific bacterial Fatty Acids (FA). Further biomarker and 16S rDNA based analyses of this horizon give evidence that AOM is mediated by archaea belonging to the ANME-1b group and Sulphate Reducing Bacteria (SRB) most likely belonging to the Seep-SRB1 cluster. The zone of active methane consumption was restricted to a distinct horizon of about 20 cm. Concentrations of 13C-depleted lipid biomarkers (e.g. 500 ng g-dw−1 biphythanes, 140 ng g-dw−1 fatty acid ai-C15:0), cell numbers (1.5×108 cells cm−3), AOM and SR rates (3 nmol cm−3 d−1) in the Tommeliten AOM zone are 2–3 orders of magnitude lower compared to AOM zones of highly active deep water cold seeps such as Hydrate Ridge or the Gulf of Mexico.

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Abstract. Initial soil development and enhanced nutrient retention are often important underlying environmental factors during primary succession. We quantified the accumulation rates of nitrogen (N) and soil organic matter (SOM) in a 37-year-long chronosequence of Leymus arenarius dunes on the pristine volcanic island Surtsey in order to illuminate the spatiotemporal patterns in their build-up. The Leymus dune area, volume and height grew exponentially over time. Aboveground plant biomass, cover or number of shoots per unit area did not change significantly with time, but root biomass accumulated with time, giving a root / shoot ratio of 19. The dunes accumulated on average 6.6 kg N ha−1 year−1, which was 3.5 times more than is received annually by atmospheric deposition. The extensive root system of Leymus seems to effectively retain and accumulate a large part of the annual N deposition, not only deposition directly on the dunes but also from the adjacent unvegetated areas. SOM per unit area increased exponentially with dune age, but the accumulation of roots, aboveground biomass and SOM was more strongly linked to soil N than time: a 1 g m−2 increase in soil N led on average to a 6 kg C m−2 increase in biomass and SOM. The Leymus dunes, where most of the N has been accumulated, will therefore probably act as hot spots for further primary succession of flora and fauna on the tephra sands of Surtsey.

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Samples were collected from 228 soils from the main agricultural areas of Western Australia (W.A.) and their chemical and textural properties analysed. Soils were incubated for 7 days with North Carolina rock phosphate at a rate equivalent to 1022 �g Ca g(-1) and 383 �g P g(-1) soil. Subsequently, the amount of rock phosphate (RP) that had dissolved was determined by measuring the increase in extractable calcium (�Ca) and changes in plant-available P were estimated by a sodium bicarbonate extraction (�Bic-P). Only 29 soils dissolved more than 40% of the added RP and these occur in the wettest area of W.A., to the west of the 800 mm rainfall isohyet. They represent a variety of soil types including Vertisols, Spodosols, Alfisols and Ultisols. Simple and multiple regressions were carried out to investigate the soil properties responsible for RP dissolution and associated P availability. No single soil property adequately predicted RP dissolution or concomitant changes in bicarbonate-P. Titratable acidity and sand content together explained 61% of the variance in RP dissolution; titratable acidity was the most predictive single variable for bicarbonate-P but only explained 56% of the variance. Stepwise regression showed that titratable acidity and pH(CaCl2) together explained 79% of the variance in bicarbonate-P. The most suitable soils for RP application are sandy, humic or peaty podzols where much of the dissolved P remains available to plants. The other soils (mainly red and yellow earths and Vertisols) which dissolved much RP contain larger amounts of extractable aluminium (by dithionite or oxalate) which is the soil component largely responsible for P-sorption in these W.A. soils. These results indicate that RP fertilizers will be most effective on the humic, sandy podzols of the western and southern coastal plains of WA.

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Abstract. Rates of denitrification in sediments were measured with the isotope pairing technique at different sites in the southern and central Baltic Sea. The rates varied between 0.5 μmol N m−2 h−1 in sands and 28.7 μmol N m−2 h−1 in muddy sediments and showed a good correlation to the organic carbon contents of the surface sediments. N-removal rates via sedimentary denitrification were estimated for the entire Baltic Sea calculating sediment specific denitrification rates and interpolating them to the whole Baltic Sea area. Another approach was carried out by using the relationship between the organic carbon content and the rate of denitrification. The N-removal by denitrification in sediments varied between 426–652 kt N a−1, which is around 48–73% of the external N inputs delivered via rivers, coastal point sources, and atmospheric deposition. Moreover, an expansion of the anoxic bottom areas was considered under the assumption of a rising oxycline from 100 to 80 m water depth. This leads to an increase of the area with anoxic conditions and an overall decrease in sedimentary denitrification by 14%. Overall, we show here that this type of data extrapolation is a powerful tool to estimate the nitrogen losses for a whole coastal sea and may be applicable to other coastal regions and enclosed seas.

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Farms for eastern oyster Crassostrea virginica, which are commonly located along shallow estuarine shores of the eastern USA, use a range of farm equipment and require regular access to care for and harvest oyster livestock. In some cases, these farms are located in areas used by Atlantic horseshoe crabs Limulus polyphemus as they come ashore during spring to spawn. The sandy shores of the Delaware Bay host the largest spawning aggregations of this species in the world. Limited studies have examined interactions between horseshoe crabs and intertidal oyster farms, and concern has been raised about the horseshoe crab’s ability to traverse oyster farms to reach spawning habitat. This study examines potential farm interactions with horseshoe crabs in Delaware Bay during the 2018 and 2019 crab spawning season. Our studies included a range of experiments and surveys during high and low tide to observe crab abundance and behavior at rack-and-bag oyster farm and non-farm sites. In all cases, results indicated that crabs can successfully traverse rack-and-bag farms and reach spawning beaches. Crabs do not differentially use farm versus non-farm areas, and crab behavior is relatively unaltered by farm gear. These results provide important context for developing frameworks for managing ecological interactions among farms and wildlife species of concern.

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Abstract. Large areas of land are restored with unweathered soil substrates following mining activities in eastern Germany and elsewhere. In the initial stages of colonization of such land by vegetation, plant roots may become key agents in generating soil formation patterns by introducing gradients in chemical and physical soil properties. On the other hand, such patterns may be influenced by root growth responses to pre-existing substrate heterogeneities. In particular, the roots of many plants were found to preferentially proliferate into nutrient-rich patches. Phosphorus (P) is of primary interest in this respect because its availability is often low in unweathered soils, limiting especially the growth of leguminous plants. However, leguminous plants occur frequently among the pioneer plant species on such soils, as they only depend on atmospheric nitrogen (N) fixation as N source. In this study we investigated the relationship between root growth allocation of the legume Lotus corniculatus and soil P distribution on recently restored land. As test sites, the experimental Chicken Creek Catchment (CCC) in eastern Germany and a nearby experimental site (ES) with the same soil substrate were used. We established two experiments with constructed heterogeneity, one in the field on the experimental site and the other in a climate chamber. In addition, we conducted high-density samplings on undisturbed soil plots colonized by L. corniculatus on the ES and on the CCC. In the field experiment, we installed cylindrical ingrowth soil cores (4.5 × 10 cm) with and without P fertilization around single two-month-old L. corniculatus plants. Roots showed preferential growth into the P-fertilized ingrowth-cores. Preferential root allocation was also found in the climate chamber experiment, where single L. corniculatus plants were grown in containers filled with ES soil and where a lateral portion of the containers was additionally supplied with a range of different P concentrations. In the high-density samplings, we excavated soil-cubes of 10 × 10 × 10 cm size from the topsoil of 3 mini-plot areas (50 × 50 cm) each on the ES and the CCC on which L. corniculatus had been planted (ES) or occurred spontaneously (CCC) and for each cube separated the soil attached to the roots (root-adjacent soil) from the remaining soil (root-distant soil). Root length density was negatively correlated with labile P (resin-extractable P) in the root-distant soil of the CCC plots and with water-soluble P in the root-distant soil of the ES plots. The results suggest that P depletion by root uptake during plant growth soon overrode the effect of preferential root allocation in the relationship between root density and plant-available soil P heterogeneity.

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Abstract. An integrated approach has been used to analyse the dependence of three Mediterranean species, A. unedo L., Q. ilex L., and P. latifolia L. co-occurring in a coastal dune ecosystem on two different water resources: groundwater and rainfed upper soil layers. The approach included leaf level gas exchanges, sap flow measurements and structural adaptations between 15 May and 31 July 2007. During this period it was possible to capture different species-specific response patterns to an environment characterized by a sandy soil, with a low water retention capacity, and the presence of a water table. The latter did not completely prevent the development of a drought response and, combined with previous studies in the same area, response differences between species have been partially attributed to different root distributions. Sap flow of A. unedo decreased rapidly with the decline of soil water content, while that of Q. ilex decreased only moderately. Midday leaf water potential of P. latifolia and A. unedo ranged between −2.2 and −2.7 MPa throughout the measuring period, while in Q. ilex it decreased down to −3.4 MPa at the end of the season. A. unedo was the only species that responded to drought with a decrease of its leaf area to sapwood area ratio from 23.9±1.2 (May) to 15.2±1.5 (July). While A. unedo also underwent an almost stepwise loss on hydraulic conductivity, such a loss did not occur for Q. ilex, whereas P. latifolia was able to slightly increase its hydraulic conducitivity. These differences show how different plant compartments coordinate differently between species in their responses to drought. The different responses appear to be mediated by different root distributions of the species and their relative resistances to drought are likely to depend on the duration of the periods in which water remains extractable in the upper soil layers.

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Imlili Sebkha is a stable and flat depression in southern Morocco that is more than 10 km long and almost 3 km wide. This region is mainly sandy, but its northern part holds permanent water pockets that contain fauna and flora despite their hypersaline water. Google Earth Engine (GEE) has revolutionized land monitoring analysis by allowing the use of satellite imagery and other datasets via cloud computing technology and server-side JavaScript programming. This work highlights the potential application of GEE in processing large amounts of satellite Earth Observation (EO) Big Data for the free, long-term, and wide spatio-temporal wet/dry permanent salt water cavities and moisture monitoring of Imlili Sebkha. Optical and radar images were used to understand the functions of Imlili Sebkha in discovering underground hydrological networks. The main objective of this work was to investigate and evaluate the complementarity of optical Landsat, Sentinel-2 data, and Sentinel-1 radar data in such a desert environment. Results show that radar images are not only well suited in studying desertic areas but also in mapping the water cavities in desert wetland zones. The sensitivity of these images to the variations in the slope of the topographic surface facilitated the geological and geomorphological analyses of desert zones and helped reveal the hydrological functions of Imlili Sebkha in discovering buried underground networks.

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Abstract. Semi-arid woodlands, which are characterised by patchy vegetation interspersed with bare, open areas, are frequently exposed to wildfire. During summer, long dry periods are occasionally interrupted by rainfall events. It is well known that rewetting of dry soil induces a flush of respiration. However, the magnitude of the flush may differ between vegetation patches and open areas because of different organic matter content, which could be further modulated by wildfire. Soils were collected from under trees, under shrubs or in open areas in unburnt and burnt sandy mallee woodland, where part of the woodland experienced a wildfire which destroyed or damaged most of the aboveground plant parts 4 months before sampling. In an incubation experiment, the soils were exposed to two moisture treatments: constantly moist (CM) and drying and rewetting (DRW). In CM, soils were incubated at 80 % of maximum water holding capacity (WHC) for 19 days; in DRW, soils were dried for 4 days, kept dry for another 5 days, then rewetted to 80 % WHC and maintained at this water content until day 19. Soil respiration decreased during drying and was very low in the dry period; rewetting induced a respiration flush. Compared to soil under shrubs and in open areas, cumulative respiration per gram of soil in CM and DRW was greater under trees, but lower when expressed per gram of total organic carbon (TOC). Organic matter content, available P, and microbial biomass C, but not available N, were greater under trees than in open areas. Wild fire decreased the flush of respiration per gram of TOC in the open areas and under shrubs, and reduced TOC and microbial biomass C (MBC) concentrations only under trees, but had little effect on available N and P concentrations. We conclude that the impact of wildfire and DRW events on nutrient cycling differs among vegetation patches of a native semi-arid woodland which is related to organic matter amount and availability.

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Abstract. What happens during primary succession after the first colonizers have occupied a pristine surface largely depends on how they ameliorate living conditions for other species. For vascular plants the onset of soil development and associated increase in nutrient (mainly nitrogen; N) and water availability is especially important. Here, we report the relationship between N accumulation and biomass and ecosystem carbon (C) stocks in a 50-year-old volcanic island, Surtsey, Iceland, where N stocks are still exceptionally low. However, a 28-year-old seagull colony on the island provided nutrient-enriched areas, which enabled us to assess the relationship between N stock and biomass and ecosystem C stocks across a much larger range in N stock. Further, we compared areas on shallow and deep tephra sands as we expected that deep-rooted systems would be more efficient in retaining N. The sparsely vegetated area outside the colony had accumulated 0.7 kg N ha−1 yr−1, which was ca. 50–60% of the estimated N input rate from wet deposition. This approximates values for systems under low N input and bare dune habitats. The seagulls have added, on average, 47 kg N ha−1 yr−1, which induced a shift from belowground to aboveground in ecosystem N and C stocks and doubled the ecosystem N-use efficiency, determined as the ratio of biomass and C storage per unit N input. Soil depth did not significantly affect total N stocks, which suggests a high N retention potential. Both total ecosystem biomass and C stocks were strongly correlated with N stock inside the colony, which indicated the important role of N during the first steps of primary succession. Inside the colony, the ecosystem biomass C stocks (17–27 ton C ha−1) had reached normal values for grasslands, while the soil organic carbon (SOC) stocks (4–10 ton C ha−1 were only a fraction of normal grassland values. Thus, it will take a long time until the SOC stock reaches equilibrium with the current primary production, during which conditions for new colonists may change.

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Abstract. Fluid flow related seafloor structures and gas seeps were detected in the North Sea in the 1970s and 1980s by acoustic sub-bottom profiling and oil rig surveys. A variety of features like pockmarks, gas vents and authigenic carbonate cements were found to be associated with sites of oil and gas exploration, indicating a link between these surface structures and the underlying, deep hydrocarbon reservoirs. In this study we performed acoustic surveys and videographic observation at Gullfaks, Holene Trench, Tommeliten, Witch's Hole and the giant pockmarks of the UK Block 15/25, to investigate the occurrence and distribution of cold seep ecosystems in the Northern North Sea. The most active gas seep sites, i.e. Gullfaks and Tommeliten, were investigated in detail. At both sites, gas bubbles escaped continuously from small holes in the seabed to the water column, reaching the upper mixed surface layer. At Gullfaks a gas emitting, flat area of 0.1 km2 of sandy seabed covered by filamentous sulfur-oxidizing bacteria was detected. At Tommeliten, we found a patchy distribution of small bacterial mats indicating sites of gas seepage. Below the patches the seafloor consisted of sand from which gas emissions were observed. At both sites, the anaerobic oxidation of methane (AOM) coupled to sulfate reduction (SR) was the major source of sulfide. Molecular analyses targeting specific lipid biomarkers and 16S rRNA gene sequences identified an active microbial community dominated by sulfur-oxidizing and sulfate-reducing bacteria (SRB) as well as methanotrophic bacteria and archaea. Stable carbon isotope values of specific, microbial fatty acids and alcohols from both sites were highly depleted in the heavy isotope 13C, indicating that the microbial community incorporates methane or its metabolites. The microbial community composition of both shallow seeps shows high similarities to the deep water seeps associated with gas hydrates such as Hydrate Ridge or the Eel River basin.

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Abstract California Grunion Leuresthes tenuis (Atherinopsidae), an indigenous endemic marine fish, makes spectacular midnight spawning runs onto sandy beaches on the Pacific coast of California and Baja California. In a unique recreational fishery, people capture the fish out of water with bare hands. Grunion hunters are not required to report their catch, and there is no bag limit. California Grunion rarely appear in trawls and do not take a hook, so population status for this species is impossible to obtain by traditional fishery methods. With citizen scientists, the “Grunion Greeters,” we monitored spawning runs along most of their habitat range. California Grunion recently underwent a northward range extension, but runs appear to be declining broadly across the core habitat. Noisy activities of recreational grunion hunters on shore disrupt spawning runs, preventing fish from reproducing before capture. Leuresthes tenuis has been identified as a Key Indicator Species for the South and Central regions of California Marine Protected Areas, and as an indicator species for climate change on beaches. Gear restrictions, license requirements, and a two-month closed season are rarely enforced late at night. We recommend continued monitoring for L. tenuis in California and increased protections for this unique charismatic fish.

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This study aims to determine the seagrass morphological characteristic based on substrates and analyze the relationship of environmental factors with the morphology of Thalassodendron ciliatum. A sampling at each station was done purposively according to the substrate. Sampling was carried out in 3 areas as replication by digging and taking seagrass complete with rhizome and its roots as many as 25 stands. Then the seagrass was cleaned from the sand and put into a sample bag and stored in a cooler. At the same time, sand and water samples were also taken to measure the nitrate and phosphate. The measured water quality in situ includes current speed, temperature, salinity, depth, and wave height. In the laboratory, measurements of morphological parameters of seagrass were done on the leaves, stems, rhizomes, and roots. The results showed that the sandy substrate (Kasuso Station: more protected) showed a longer and thicker leaf character, and a longer root with a greater number of roots, but had a number of leaves, rhizoma length, internode distance, and root diameter smaller than the area with the substrate was dominated by coral fragments (Panrangluhu Station). Under weak current conditions with high nitrate and phosphate content, they were characterized by the larger stem and leaf lengths with a large number of roots. Whereas in strong currents, seagrass was characterized by a greater number and area of leaves and root diameter. Areas with high waves, characterized by seagrasses that have larger stem diameters, longer rhizomes with larger diameters, and also longer internode distances Penelitian ini bertujuan untuk mendeterminasi karakter morfologi lamun berdasarkan tipe substrat dan menganalisis keterkaitan faktor lingkungan dengan morfologi lamun Thalassodendron ciliatum. Sampling pada setiap stasiun dilakukan secara purposif dengan memperhatikan susbstrat dasar. Sampling dilakukan pada 3 area sebagai ulangan dengan cara menggali dan mengambil lamun lengkap dengan rhizoma dan akarnya sebanyak 25 tegakan. Kemudian lamun dibersihkan dari pasir dan dimasukkan ke dalam kantong sampel yang berisi air laut dan disimpan dalam kotak pendingin. Bersamaan dengan itu, juga diambil sampel pasir dan air untuk diukur kandungan nitrat dan posfatnya. Kualitas air yang diukur secara insitu meliputi kecepatan arus, suhu, salinitas, kedalaman, dan tinggi gelombang. Di laboratorium diukur parameter morfologi lamun pada bagian daun, batang, rhizoma, dan akar. Hasil analisis menunjukkan bahwa pada substrat berpasir (Stasiun Kasuso: lebih terlindung) memperlihatkan karakter daun yang lebih panjang dan tebal, serta akar yang lebih panjang dengan jumlah akar yang lebih banyak, namun memiliki jumlah daun, panjang rhizoma, jarak internode, dan diameter akar yang lebih kecil dibandingkan dengan daerah yang substratnya didominasi oleh pecahan karang (Stasiun Panrangluhu). Pada kondisi arus yang lemah dengan kandungan nitrat dan posfat yang tinggi, dicirikan oleh panjang batang dan daun yang lebih besar dengan jumlah akar yang banyak. Sedangkan pada arus yang kuat, lamun dicirikan oleh jumlah dan luasan daun serta diameter akar yang lebih besar. Daerah dengan gelombang yang tinggi, dicirikan oleh lamun yang memiliki diameter batang yang lebih besar, rhizoma yang lebih panjang dengan diameter yang besar, dan jarak internode yang juga lebih panjang.

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Abstract. Soil surface roughness (SSR) expresses soil susceptibility to wind and water erosion and plays an important role in the development and the maintenance of soil biota. Several methods have been developed to characterise SSR based on different methods of acquiring data. Because the main problems related to these methods involve the use and handling of equipment in the field, the present study aims to fill the need for a method for measuring SSR that is more reliable, low-cost and convenient in the field than traditional field methods. Shadow analysis, which interprets micro-topographic shadows, is based on the principle that there is a direct relationship between the soil surface roughness and the shadows cast by soil structures under fixed sunlight conditions. SSR was calculated with shadows analysis in the laboratory using hemispheres of different diameter with a diverse distribution of known altitudes and a surface area of 1 m2. Data obtained from the shadow analysis were compared to data obtained with the chain method and simulation of the micro-relief. The results show a relationship among the SSR calculated using the different methods. To further improve the method, shadow analysis was used to measure the SSR in a sandy clay loam field using different tillage tools (chisel, tiller and roller) and in a control of 4 m2 surface plots divided into subplots of 1 m2. The measurements were compared to the data obtained using the chain set and pin meter methods. The SSR measured was the highest when the chisel was used, followed by the tiller and the roller, and finally the control, for each of the three methods. Shadow analysis is shown to be a reliable method that does not disturb the measured surface, is easy to handle and analyse, and shortens the time involved in field operations by a factor ranging from 4 to 20 compared to well known techniques such as the chain set and pin meter methods.

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Abstract. Permafrost ground is one of the largest repositories of terrestrial organic carbon and might become or already is a carbon source in response to ongoing global warming. With this study of syngenetically frozen, ice-rich and organic carbon (OC)-bearing Yedoma and associated alas deposits in central Yakutia (Republic of Sakha), we aimed to assess the local sediment deposition regime and its impact on permafrost carbon storage. For this purpose, we investigated the Yukechi alas area (61.76495∘ N, 130.46664∘ E), which is a thermokarst landscape degrading into Yedoma in central Yakutia. We retrieved two sediment cores (Yedoma upland, 22.35 m deep, and alas basin, 19.80 m deep) in 2015 and analyzed the biogeochemistry, sedimentology, radiocarbon dates and stable isotope geochemistry. The laboratory analyses of both cores revealed very low total OC (TOC) contents (<0.1 wt %) for a 12 m section in each core, whereas the remaining sections ranged from 0.1 wt % to 2.4 wt % TOC. The core sections holding very little to no detectable OC consisted of coarser sandy material were estimated to be between 39 000 and 18 000 BP (years before present) in age. For this period, we assume the deposition of organic-poor material. Pore water stable isotope data from the Yedoma core indicated a continuously frozen state except for the surface sample, thereby ruling out Holocene reworking. In consequence, we see evidence that no strong organic matter (OM) decomposition took place in the sediments of the Yedoma core until today. The alas core from an adjacent thermokarst basin was strongly disturbed by lake development and permafrost thaw. Similar to the Yedoma core, some sections of the alas core were also OC poor (<0.1 wt %) in 17 out of 28 samples. The Yedoma deposition was likely influenced by fluvial regimes in nearby streams and the Lena River shifting with climate. With its coarse sediments with low OC content (OC mean of 5.27 kg m−3), the Yedoma deposits in the Yukechi area differ from other Yedoma sites in North Yakutia that were generally characterized by silty sediments with higher OC contents (OC mean of 19 kg m−3 for the non-ice wedge sediment). Therefore, we conclude that sedimentary composition and deposition regimes of Yedoma may differ considerably within the Yedoma domain. The resulting heterogeneity should be taken into account for future upscaling approaches on the Yedoma carbon stock. The alas core, strongly affected by extensive thawing processes during the Holocene, indicates a possible future pathway of ground subsidence and further OC decomposition for thawing central Yakutian Yedoma deposits.

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Abstract. Surface sediments from sites across the Indian margin of the Arabian Sea were analysed for their elemental and stable isotopic organic carbon (Corg) and total nitrogen compositions, grain size distributions and biochemical indices of organic matter (OM) source and/or degradation state. Site locations ranged from the estuaries of the Mandovi and Zuari rivers to depths of ~ 2000 m on the continental slope, thus spanning nearshore muds and sands on the shelf and both the oxygen minimum zone (OMZ) on the upper slope (~ 200–1300 m) and the seasonal hypoxic zone that appears on the shelf. Source indices showed mixed marine and terrigenous OM within the estuaries, but consistent predominance (80–100%) of marine OM on the shelf and slope. Thus, riverine terrigenous OM is diluted or replaced by autochthonous marine OM and/or is efficiently re-mineralised, within or immediately offshore of the estuaries. Organic C contents of surface shelf sediments varied from < 0.5 wt% in relict shelf sands to up to ~ 4 wt% for nearshore muds, while upper slope sites within the OMZ showed a wide range (~ 2 to 7 + wt%), progressively decreasing below the OMZ to ≤ 1 wt% at 2000 m. Thus, major variability (~ 5 wt%) was found at slope sites within the OMZ of similar depth and near-identical bottom-water O2 concentrations. A strong relationship between %Corg and sediment grain size was seen for sediments within the OMZ, but lower relative Corg contents were found for sites on the shelf and below the OMZ. Further, Corg loadings, when related to estimated sediment surface area, indicated distinct enrichment of Corg in the OMZ sediments relative to sites above and below the OMZ and to sediments from normoxic margins. Diagenetic indices confirmed that lower Corg content below the OMZ is associated with more extensive OM degradation, but that shelf sediment OM is not consistently more degraded than that found within the OMZ. Together, the results indicate that OM distribution across the margin is controlled by interplay between hydrodynamic processes and varying preservation associated with O2 availability. This inference is supported by multiple regression analysis. Hydrodynamic processes (expressed as %Silt) followed by O2 availability, can explain the large majority of %Corg variability when the shelf and slope are considered as a whole. However, while O2 becomes the primary influence on %Corg for sediments below the OMZ, %Silt is the primary influence across the OMZ and, apparently, the shelf. Thus, reduced O2 exposure is responsible for OM enrichment within the OMZ, but hydrodynamic processes are the overriding control on sediment OM distributions across both the shelf and the OMZ.